101
votes
Accepted
Can HIV be transmitted via mosquitos?
No, this is not possible. There are a few reasons for that, but most important are that the only thing a mosquito injects is its own saliva, while the blood is sucked into the stomach where it is ...
- 51.5k
54
votes
What is the benefit of fever during infections?
Fever is a trait observed in warm and cold-blooded vertebrates that has been conserved for hundreds of millions of years (Evans, 2015).
Elevated body temperature stimulates the body's immune ...
- 52.3k
43
votes
Accepted
Why do diseases in the tap water of developing countries affect people from developed countries more?
You can expect that someone drinking from a water source regularly will develop immunity to the pathogens in that water source by being repeatedly exposed to them.
However, it's not quite right to say ...
- 44.1k
36
votes
Accepted
Specific mechanism behind lethality of yellow coat color in mice
Really interesting question: The lethal yellow mutation (also abbreviated Ay) affects the agouti signalling protein which plays a major role in pigmentation. Heterozygous expression of it leads to the ...
- 51.5k
18
votes
Accepted
Why is an HIV infection considered "incurable"?
The reasons why HIV is "incurable" (a misnomer) are legion:
HIV is a retrovirus, which means it inserts its own genome into the host cell's genome. You must therefore kill each and every infected ...
- 9,681
18
votes
Why doesn't blood remain on a mosquito's proboscis in quantities that could spread blood-borne diseases?
A mosquito's proboscis isn't like that of a butterfly, which could easily have nectar clinging to it when it is coiled up; instead, consider that the part of the mosquito's proboscis that enters a ...
- 24.7k
18
votes
Accepted
Is COVID-19 claimed to get less deadly over time? If so, why?
While the data are much too sparse and noisy to give an answer about what is happening to COVID-19's virulence (the technical term for the "deadliness" of an infectious disease), or to forecast what ...
- 5,324
15
votes
Accepted
Can cancers caused due to viruses be contagious?
The question title and the question itself ask two slightly (but critically) different questions.
Can cancers caused due to viruses be contagious? NO
Are these oncoviruses infectious in nature? YES
...
- 14.2k
14
votes
Accepted
Do colour-blind people see white?
It's definitely not white or grey generally, it's a mix of other colors, they often have low resolution of a particular color so that it's less visible rather than visible and grey.
Here's a page ...
- 10.3k
13
votes
Can HIV be transmitted via mosquitos?
I am not a medical doctor but in my view this is within the realms of possibility. The probability has been estimated by Princeton at 1 in 10 million. This is per bite, assuming - I presume - that the ...
12
votes
Can cancers caused due to viruses be contagious?
Yes, Oncoviruses are infectious in nature. A good example is the Human Papilloma Virus, which does not immediately cause cancer, but can cause precancerous lesions in infected regions including cervix,...
- 51.5k
12
votes
Accepted
Does the recent concern over several papers about Aβ*56 call into question the association of Alzheimers Disease with any amyloyd beta oligomer forms?
Does the recent concern over several papers about Aβ*56 call into question the association of Alzheimers Disease with any amyloyd beta oligomer forms?
From my understanding, no. alzforum.org has ...
- 1,855
11
votes
Accepted
Why does a Urinary Tract Infection cause a strong, persistent urge to urinate?
Nerve endings exist in a more or less homeostatic interstitial fluid medium which when disturbed in certain ways result in depolarization. This is a very simple explanation, but basically correct. ...
- 24.7k
11
votes
Why are men more susceptible to severe COVID-19?
Update -- In the time since this question was asked, two relevant articles have been published, one in Nature Reviews Immunology and one in medRxiv (note: medRxiv is a preprint server and is therefore ...
- 8,266
9
votes
Accepted
Why is the species-diversity of deadly parasites greatest in the tropics?
The diversity of parasites shows a gradient with increasing diversity from the poles to the equator. Several reasons have been brought forth to explain the latitude-dependency of parasite diversity:
...
- 52.3k
8
votes
Accepted
Why don't we build up an immunity to sore throat?
Short Answer
It should be noted that there are many non-pathogenic causes of sore throat, and I would suspect that you are not always distinguishing these causes from actual illness.
In most cases, ...
- 29.7k
8
votes
Accepted
how the coronavirus was distinguished?
This is basic epidemiology. When medical professionals notice that a group of people with some characteristic in common, are being seen for a similar disease, they ask if there's a connection. In this ...
- 14.2k
7
votes
Accepted
How "exactly" is Rabies transmitted?
This is actually far more complex a question than you probably know. The country you are writing from matters. There are some rabies virus variants that have a relatively low pathogenicity for humans (...
- 24.7k
7
votes
Spread of malaria from an infected person
With humans infected with malaria, the parasite load in the blood can be quite high. It ranges from 10 to 108 Plasmodium falciparum parasites per ml .
When a female Anopheles mosquito bites an ...
- 2,258
7
votes
Accepted
What causes the range of severity of neurological deficits in Down's syndrome?
The symptoms of Down syndrome occur due to overexpression of genes present on the duplicated chromosome.
If possessing an extra chromosome meant an equivalent change in gene expression, one would ...
- 44.1k
7
votes
Accepted
Why doesn't blood remain on a mosquito's proboscis in quantities that could spread blood-borne diseases?
What you're talking about is called mechanical transmission (at least in veterinary and medical circles; plant epidemiologists call it something different). There's a nice overview by Gray and ...
- 3,346
7
votes
What is the benefit of fever during infections?
Fever normally under hypothalamic heat center's control which stays at limbic system of brain . Hypothalamus sets its own set point 36.4-37.2 in healthy peoples by some molecules named exogenous and ...
- 91
7
votes
Accepted
What is "multiple" myeloma?
J. Von Rustizky, a Russian pathologist working in the laboratory of Friedrich von Recklinghausen (1833–1910) in Strassburg in 1873, introduced the term “multiple myeloma.” At autopsy, a 47-year-old ...
- 22.7k
7
votes
Why does this plum/apricot hybrid look like brains?
It is difficult to say, but it is likely due to disease. Many plant diseases have the effect of convincing plant tissues that they are some other organ than what they actually are, which leads to ...
- 9,162
7
votes
Longevity and extent of transfection after SARS-COV-2 vaccination with Janssen
Both the AstraZeneca (AZ) and Janssen (J) vaccines against SARS-CoV-2 work by using what is known as a viral vector to generate an immune response. In both cases these vaccines use an Adenovirus as ...
- 11.2k
7
votes
Accepted
Can plants be pathogenic towards humans?
Yes: Protothecosis is infection of the bloodstream by a genus of non-green algae. There are also odd reports of infection by green algae, such as this one.
- 11.2k
6
votes
Accepted
How plasma cells switches secreting different Ig classes?
In T-dependent antigen recognition, the B cell can switch the isotype by first altering the heavy chain gene. This is driven by Tfh cells. The specific cytokine stimulating the class switch determines ...
- 8,101
6
votes
How to find mutations related to disease for a protein?
I think I understand what you are asking so I will make a little guide to find what you need:
NOTE the mutations you are searching for are probably on gene level so you can search your protein on ...
- 2,380
6
votes
Accepted
Can a human actually be "frightened to death?"
The people whom this happens to consider themselves average people.
The thought is that catecholamine surge caused by the event triggers some predisposition to cardiac arrhythmia - maybe inherited, ...
- 2,964
6
votes
Why exactly does the immune system weaken with age?
We don't know.
More precisely, we know of many, many different reasons why the immune system deteriorates with age, but we don't really know which are different measures of the same thing, which ...
- 14.2k
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